Spatial magnetic properties subject to lone pair and pi electron delocalization in benzenoid and quinoid structures are quinoid tautomers really nonaromatic?
- The spatial magnetic properties, through-space NMR shieldings (TSNMRS), of benzenoid and quinoid tautomeric structures such as benzodifurantrione and phenazine-type molecules have been calculated using the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept of Paul von Rague Schleyer and visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. The TSNMRS values were employed to quantify and visualize the partial aromaticity of the studied compounds. In the case of the surprisingly more stable quinoid tautomers, the aromaticity-synonymous with stability due to the conjugation of p electrons and lone pairs-was not found to be particularly reduced.
Author details: | Erich KleinpeterORCiDGND, Andreas KochORCiDGND |
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ISSN: | 1551-7004 |
Title of parent work (English): | Arkivoc : free online journal of organic chemistry |
Publisher: | ARKAT |
Place of publishing: | Gainesville |
Publication type: | Article |
Language: | English |
Year of first publication: | 2012 |
Publication year: | 2012 |
Release date: | 2017/03/26 |
Tag: | GIAO; NICS; Through-space NMR shieldings (TSNMRS); aromaticity; benzenoid structures; quinoid structures |
Number of pages: | 15 |
First page: | 94 |
Last Page: | 108 |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Chemie |
Peer review: | Referiert |